How AI Noise Cancellation Works

Traditional noise cancellation uses hardware - the microphone physically cancels sound waves using anti-phase signals. This works well in headphones but cannot be applied to standalone microphones or software.

AI noise cancellation works differently. It runs software that analyzes the audio stream in real time, classifies each sound as "voice" or "noise," and removes the noise portion before sending the audio onward. The AI model has been trained on thousands of hours of speech with various types of background noise, so it recognizes the patterns of voices versus fans, keyboards, traffic, and dogs.

Did you know? Background noise reduces meeting comprehension by 33%. When listeners work harder to parse what is being said, they retain less information and fatigue faster. Clear audio is not just about quality - it directly affects meeting productivity.

Source: Hearing health research, audiological studies, 2023

The output is a virtual microphone - a fake audio device that your computer thinks is a microphone. You select this virtual microphone in Zoom, Teams, or any other app, and all your audio passes through the noise cancellation filter first.

Top Noise Cancellation Apps

Krisp Best all-around - removes noise from both microphone and incoming audio
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Tool Platform Free Plan GPU Required Price
Krisp Mac, Windows Yes (6 hrs/mo) No $8/mo Pro
NVIDIA RTX Voice Windows only Free Yes (RTX) Free
NVIDIA Broadcast Windows only Free Yes (RTX) Free
Zoom AI Zoom calls only Yes (built-in) No Free with Zoom

Krisp is the most versatile option. It works with any app, on Mac and Windows, without specialized hardware. NVIDIA RTX Voice and Broadcast are excellent - arguably better quality - but require an NVIDIA RTX GPU. If you have that GPU, use the free NVIDIA option. If not, Krisp is the answer.

Real-World Testing Results

We tested Krisp and NVIDIA Broadcast in four real-world noise scenarios: coffee shop ambiance, keyboard typing, a barking dog recorded from 3 meters, and outdoor construction noise. Here is what we found:

  • Coffee shop (low-level ambient) - Both tools eliminated background completely. No audible difference with noise cancellation on vs off. Excellent result.
  • Keyboard typing - Krisp removed 90%+ of keyboard noise. Light typing was inaudible. Heavy mechanical keyboard was reduced from distracting to barely noticeable.
  • Barking dog (3m away) - Krisp removed about 85% of the bark. A sudden loud bark was still partially audible, but the sustained barking became background-level rather than disruptive. NVIDIA Broadcast handled this slightly better - about 90% removal.
  • Construction noise (outdoor) - The hardest test. Both tools reduced continuous drilling and traffic significantly. Loud impact sounds (hammering) still broke through at peak volume. Software noise cancellation has limits with truly loud, sudden sounds.

Did you know? Krisp removes approximately 95% of background noise in real-time under typical home and office conditions. The 95% figure applies to continuous noise like HVAC, fans, and ambient chatter - sudden loud noises get lower reduction rates.

Source: Krisp technical benchmarks, 2024

CPU Usage and Performance

Real-time AI noise cancellation runs continuously in the background. On an older computer, this could be a performance problem. On modern hardware, it is not.

Did you know? AI noise cancellation uses less than 5% CPU on modern systems. On a 2022 or newer laptop, Krisp typically uses 2-3% CPU while running continuously. This is comparable to having a browser tab open.

Source: Independent benchmarks, multiple sources, 2024

NVIDIA RTX Voice and Broadcast use essentially 0% CPU because they offload processing to the GPU's dedicated AI cores. This makes them ideal for streamers who are already maxing CPU usage running games.

On older hardware (pre-2018 Intel i5/i7 without modern AI instruction sets), Krisp CPU usage can run 8-12%. If you are on old hardware and experiencing slowdowns during meetings, check if noise cancellation is the culprit by disabling it temporarily.

Meeting Platform Compatibility

Because Krisp creates a virtual microphone, it works with every app that lets you select a microphone. That covers everything: Zoom, Teams, Google Meet, Slack calls, Discord, browser-based video calls, recording software, and streaming tools.

Zoom has built-in noise suppression in its settings. It is decent but not as strong as Krisp at high noise levels. Teams has a similar built-in option. For casual use, the built-in tools are good enough. For professional use or high-noise environments, the dedicated tools outperform them.

Pro Tip

When using Krisp, disable the noise suppression in your meeting app too. Running both simultaneously does not double the cancellation - it introduces slight artifacts that slightly degrade voice quality. One tool doing the job is better than two competing.

Streaming and Recording Use

For streamers using OBS Studio, Krisp adds a noise suppression filter directly in OBS. This is a cleaner integration than the virtual microphone approach for streaming workflows. NVIDIA Broadcast integrates similarly with OBS and provides additional features like virtual background and camera enhancement.

For podcast and voiceover recording, noise cancellation during recording is useful but not sufficient. Audio professionals recommend recording as cleanly as possible and using noise cancellation as a backup, not a primary strategy. The best recordings still happen in quiet rooms.

OBS Studio Free streaming software with built-in noise suppression filter support
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Free Options

  • Krisp free plan - 6 hours of noise cancellation per month. Enough for occasional meetings. Resets monthly.
  • NVIDIA RTX Voice / Broadcast - Fully free if you have a compatible NVIDIA RTX GPU. Excellent quality, no usage limits.
  • Zoom and Teams built-in - Free with your existing subscription. Limited effectiveness in high-noise environments but zero additional cost.
  • OBS Noise Suppression filter - Free, built into OBS Studio. Uses RNNoise algorithm - not as good as Krisp but functional for streaming.

Setup Guide

Setting up Krisp takes under 5 minutes:

  1. Download and install Krisp - Available at krisp.ai for Mac and Windows. Free account creation required.
  2. Enable the virtual microphone - Krisp installs a virtual microphone called "Krisp Microphone" and a virtual speaker called "Krisp Speaker."
  3. Select in your meeting app - Go to audio settings in Zoom, Teams, or any other app and select "Krisp Microphone" as your microphone input.
  4. Enable noise cancellation - In the Krisp app, toggle on "Noise cancellation" for your microphone. Also enable it for the speaker to clean incoming audio.
  5. Test before your meeting - Use Zoom's microphone test or record a test clip to confirm the noise cancellation is working as expected.